The value at the end of the year is 100% - 20% = 0.80 of the value at the beginning of the year. After 4 years of multiplying by this factor, the value is
$17,500·0.80⁴ = $7,168
Answer:
C
Step-by-step explanation:
Given 2 secants intersect a circle from a point outside the circle, then
The product of the external part and the entire part of one secant is equal to the product of the external part and the entire part of the other secant, that is
x(x + 10 + x) = 6(6 + 10 + x)
x(2x + 10) = 6(16 + x) ← distribute parenthesis on both sides
2x² + 10x = 96 + 6x ← subtract 96 + 6x from both sides
2x² + 4x - 96 = 0 ← in standard form
Divide through by 2
x² + 2x - 48 = 0 ← factor the left side
(x + 8)(x - 6) = 0
Equate each factor to zero and solve for x
x + 8 = 0 ⇒ x = - 8
x - 6 = 0 ⇒ x = 6
However x > 0 ⇒ x = 6 → C
Answer:
2 gallons of pure alcohol
Step-by-step explanation:
Let x represent the number of gallons of pure alcohol needed, and create an equation:
4(0.25) + x(1) = (x + 4)0.5
1 + x = 0.5x + 2
x = 0.5x + 1
0.5x = 1
x = 2
So, 2 gallons of pure alcohol should be added.
